Merge branch 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux

Pull removal of in-kernel calls to syscalls from Dominik Brodowski:
 "System calls are interaction points between userspace and the kernel.
  Therefore, system call functions such as sys_xyzzy() or
  compat_sys_xyzzy() should only be called from userspace via the
  syscall table, but not from elsewhere in the kernel.

  At least on 64-bit x86, it will likely be a hard requirement from
  v4.17 onwards to not call system call functions in the kernel: It is
  better to use use a different calling convention for system calls
  there, where struct pt_regs is decoded on-the-fly in a syscall wrapper
  which then hands processing over to the actual syscall function. This
  means that only those parameters which are actually needed for a
  specific syscall are passed on during syscall entry, instead of
  filling in six CPU registers with random user space content all the
  time (which may cause serious trouble down the call chain). Those
  x86-specific patches will be pushed through the x86 tree in the near
  future.

  Moreover, rules on how data may be accessed may differ between kernel
  data and user data. This is another reason why calling sys_xyzzy() is
  generally a bad idea, and -- at most -- acceptable in arch-specific
  code.

  This patchset removes all in-kernel calls to syscall functions in the
  kernel with the exception of arch/. On top of this, it cleans up the
  three places where many syscalls are referenced or prototyped, namely
  kernel/sys_ni.c, include/linux/syscalls.h and include/linux/compat.h"

* 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux: (109 commits)
  bpf: whitelist all syscalls for error injection
  kernel/sys_ni: remove {sys_,sys_compat} from cond_syscall definitions
  kernel/sys_ni: sort cond_syscall() entries
  syscalls/x86: auto-create compat_sys_*() prototypes
  syscalls: sort syscall prototypes in include/linux/compat.h
  net: remove compat_sys_*() prototypes from net/compat.h
  syscalls: sort syscall prototypes in include/linux/syscalls.h
  kexec: move sys_kexec_load() prototype to syscalls.h
  x86/sigreturn: use SYSCALL_DEFINE0
  x86: fix sys_sigreturn() return type to be long, not unsigned long
  x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm()
  mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead()
  mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff()
  mm: add ksys_fadvise64_64() helper; remove in-kernel call to sys_fadvise64_64()
  fs: add ksys_fallocate() wrapper; remove in-kernel calls to sys_fallocate()
  fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls
  fs: add ksys_truncate() wrapper; remove in-kernel calls to sys_truncate()
  fs: add ksys_sync_file_range helper(); remove in-kernel calls to syscall
  kernel: add ksys_setsid() helper; remove in-kernel call to sys_setsid()
  kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare()
  ...

1 files changed, 19 insertions, 18 deletions

diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index 79b7a3438d54..8ac38d51ed7d 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -89,18 +89,18 @@
 COMPAT_SYSCALL_DEFINE3(s390_chown16, const char __user *, filename,
 		       u16, user, u16, group)
 {
-	return sys_chown(filename, low2highuid(user), low2highgid(group));
+	return ksys_chown(filename, low2highuid(user), low2highgid(group));
 }
 
 COMPAT_SYSCALL_DEFINE3(s390_lchown16, const char __user *,
 		       filename, u16, user, u16, group)
 {
-	return sys_lchown(filename, low2highuid(user), low2highgid(group));
+	return ksys_lchown(filename, low2highuid(user), low2highgid(group));
 }
 
 COMPAT_SYSCALL_DEFINE3(s390_fchown16, unsigned int, fd, u16, user, u16, group)
 {
-	return sys_fchown(fd, low2highuid(user), low2highgid(group));
+	return ksys_fchown(fd, low2highuid(user), low2highgid(group));
 }
 
 COMPAT_SYSCALL_DEFINE2(s390_setregid16, u16, rgid, u16, egid)
@@ -302,12 +302,12 @@ COMPAT_SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, compat_ulong_t, second,
 
 COMPAT_SYSCALL_DEFINE3(s390_truncate64, const char __user *, path, u32, high, u32, low)
 {
-	return sys_truncate(path, (unsigned long)high << 32 | low);
+	return ksys_truncate(path, (unsigned long)high << 32 | low);
 }
 
 COMPAT_SYSCALL_DEFINE3(s390_ftruncate64, unsigned int, fd, u32, high, u32, low)
 {
-	return sys_ftruncate(fd, (unsigned long)high << 32 | low);
+	return ksys_ftruncate(fd, (unsigned long)high << 32 | low);
 }
 
 COMPAT_SYSCALL_DEFINE5(s390_pread64, unsigned int, fd, char __user *, ubuf,
@@ -315,7 +315,7 @@ COMPAT_SYSCALL_DEFINE5(s390_pread64, unsigned int, fd, char __user *, ubuf,
 {
 	if ((compat_ssize_t) count < 0)
 		return -EINVAL;
-	return sys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low);
+	return ksys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low);
 }
 
 COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubuf,
@@ -323,12 +323,12 @@ COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubu
 {
 	if ((compat_ssize_t) count < 0)
 		return -EINVAL;
-	return sys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low);
+	return ksys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low);
 }
 
 COMPAT_SYSCALL_DEFINE4(s390_readahead, int, fd, u32, high, u32, low, s32, count)
 {
-	return sys_readahead(fd, (unsigned long)high << 32 | low, count);
+	return ksys_readahead(fd, (unsigned long)high << 32 | low, count);
 }
 
 struct stat64_emu31 {
@@ -442,8 +442,8 @@ COMPAT_SYSCALL_DEFINE1(s390_old_mmap, struct mmap_arg_struct_emu31 __user *, arg
 		return -EFAULT;
 	if (a.offset & ~PAGE_MASK)
 		return -EINVAL;
-	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
-			      a.offset >> PAGE_SHIFT);
+	return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+			       a.offset >> PAGE_SHIFT);
 }
 
 COMPAT_SYSCALL_DEFINE1(s390_mmap2, struct mmap_arg_struct_emu31 __user *, arg)
@@ -452,7 +452,7 @@ COMPAT_SYSCALL_DEFINE1(s390_mmap2, struct mmap_arg_struct_emu31 __user *, arg)
 
 	if (copy_from_user(&a, arg, sizeof(a)))
 		return -EFAULT;
-	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
+	return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
 }
 
 COMPAT_SYSCALL_DEFINE3(s390_read, unsigned int, fd, char __user *, buf, compat_size_t, count)
@@ -460,7 +460,7 @@ COMPAT_SYSCALL_DEFINE3(s390_read, unsigned int, fd, char __user *, buf, compat_s
 	if ((compat_ssize_t) count < 0)
 		return -EINVAL; 
 
-	return sys_read(fd, buf, count);
+	return ksys_read(fd, buf, count);
 }
 
 COMPAT_SYSCALL_DEFINE3(s390_write, unsigned int, fd, const char __user *, buf, compat_size_t, count)
@@ -468,7 +468,7 @@ COMPAT_SYSCALL_DEFINE3(s390_write, unsigned int, fd, const char __user *, buf, c
 	if ((compat_ssize_t) count < 0)
 		return -EINVAL; 
 
-	return sys_write(fd, buf, count);
+	return ksys_write(fd, buf, count);
 }
 
 /*
@@ -483,7 +483,8 @@ COMPAT_SYSCALL_DEFINE5(s390_fadvise64, int, fd, u32, high, u32, low, compat_size
 		advise = POSIX_FADV_DONTNEED;
 	else if (advise == 5)
 		advise = POSIX_FADV_NOREUSE;
-	return sys_fadvise64(fd, (unsigned long)high << 32 | low, len, advise);
+	return ksys_fadvise64_64(fd, (unsigned long)high << 32 | low, len,
+				 advise);
 }
 
 struct fadvise64_64_args {
@@ -503,19 +504,19 @@ COMPAT_SYSCALL_DEFINE1(s390_fadvise64_64, struct fadvise64_64_args __user *, arg
 		a.advice = POSIX_FADV_DONTNEED;
 	else if (a.advice == 5)
 		a.advice = POSIX_FADV_NOREUSE;
-	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
+	return ksys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
 }
 
 COMPAT_SYSCALL_DEFINE6(s390_sync_file_range, int, fd, u32, offhigh, u32, offlow,
 		       u32, nhigh, u32, nlow, unsigned int, flags)
 {
-	return sys_sync_file_range(fd, ((loff_t)offhigh << 32) + offlow,
+	return ksys_sync_file_range(fd, ((loff_t)offhigh << 32) + offlow,
 				   ((u64)nhigh << 32) + nlow, flags);
 }
 
 COMPAT_SYSCALL_DEFINE6(s390_fallocate, int, fd, int, mode, u32, offhigh, u32, offlow,
 		       u32, lenhigh, u32, lenlow)
 {
-	return sys_fallocate(fd, mode, ((loff_t)offhigh << 32) + offlow,
-			     ((u64)lenhigh << 32) + lenlow);
+	return ksys_fallocate(fd, mode, ((loff_t)offhigh << 32) + offlow,
+			      ((u64)lenhigh << 32) + lenlow);
 }